<?php
/**
 * Created by PhpStorm.
 * User: wangye
 * Date: 19-3-5
 * Time: 上午9:50
 */

// open_door make_by_id

function strHandle($str) {
    $return = '';
    $arr = explode('_',$str);
    foreach ($arr as $value) {
        $return .= ucfirst($value);
    }
    return $return;
}
$str1 = 'make_by_id';
echo strHandle($str1);